The Black Eyed Peas’ “I Gotta Feeling” (2009) is an upbeat party anthem that defined the sound of late-2000s pop. Produced by David Guetta, the song’s optimistic lyrics and pounding electro-pop beat (“Tonight’s gonna be a good night”) made it a universal celebratory anthem. It topped the Hot 100 for 14 weeks, and its infectious, feel-good energy has made it a staple at weddings, sporting events, and any occasion that calls for a communal sing-along.